1,1-Dimethylethyl (3R)-3-aminobutanoate → (r)-3-((s)-2-(4,4-Bis(trifluoromethyl)-3-(4-(3-(2-methylphenyl)ureido)-3-methoxy-benzyl)-2,5-dioxoimidazolidin-1-yl)-2-(2-methylpropyl) acetylamino)-3-methylpropionic acid

Participants

Reaction Steps

which had been prepared from (S)-2-(4,4-bis(trifluoromethyl)-2,5-dioxoimidazolidin-1-yl)-2-(2-methylpropyl)acetic acid and 4-(3-(2-methylphenyl)ureido)-3-methoxybenzyl chloride as described in Example 18f, and 128 mg (0.809 mmol) of tert-butyl (R)-3-aminobutanoate. After coupling, chromatographic purification over silica gel (eluent: heptane/ethyl acetate=3/2) and cleavage of the tert-butyl ester, 299 mg (53%) of the title compound were obtained.

Provenance & Evidence